Electric motor.



PATENTED MAR. 7, 1905.

W. A. LAYMAN.

ELECTRIC MOTOR. APPLIUATION FILED DB0. 2s, 190s. BBNBWED AUG. 25, 1904.

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Waldo. A. Layman. my v/M No. 784,056. PATENTED MAR. 7, 1905. W. A.LAYMAN.

ELECTRIC MOTOR.

APPLIGATION FILED DBG. 28. 1903. RENEWED AUG. 25, 1904.

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ELECTRIC MOTOR.

APPLICATION FILED 11,110.28, 1903. Bmsmwnn AUG. 25, 1904.

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PATENT OEEicE.

ELECTRIC MOTOR.

SPECIFICATION forming part of Letters Patent No. 784,056, dated March 7,1905.

Application filed December 23, 1903. Renewed August 25. 1904. Sei'iaINo. 222,136.

To all 7071/0711/ it mfny/ con/cern,.-

Be it known that I, WALDo A. LAYMAN, a citizen of the United States,residing at the city of St. Louis, in the State of Missouri, haveinvented a certain new and useful Electric Motor, ofwhich the followingis such a full, clear, and exact description as will enable'any oneskilled in the art to which it appertains to make and use the same,reference being had to the accompanying drawings, forming part of thisspecification.

My invention relates to electric motors, and more particularly to thattype of alternating-current motors in which the armature is providedwith a circuit coinmuted at starting for producing definitearmaturepoles and with means, preferably automatic, for shoit-circuitingthe individual coils of the armature after starting.

One object of my invention is to combine in an alternating-current motorthe ability to operate at speeds below the normal running speed and atthe same time to secure at normal speed the maximum output of which thewindings are capable.

I provide the armature of my motor at normal running speed with a largenumber of short circuits7 thus decreasing the resistance of the armaturewinding or windings and securing a motor of greater capacity than hasheretofore been obtained in this type.

In the accompanying drawings, Figure I is a diagram showing thepreferred form of my invention. Fig. 2 is a vertical section showing themechanical construction of a V motor to which my invention is applied,and

Figs. 3 and 4 are diagrams showing certain modifications.

Like marks of reference referto similar parts in the several views ofthe drawings.

represents the field-cores wound with field-coils 11. These field-coils11 are supplied with single-phase alternating current from mains 12.

14 is the core ofthe armature supplied with suitable windings 15. Thesewindings 15 are connected by means of leads 16 with commutator-segments17. Bearing on the segments 1.7 are brushes 1S, connected by a conductor19.

is a contact-ring for short-circuiting the individual coils of thewinding 15 by contact with terminals 2l.

22 is a symmetrical three-part resistance which is connected to thewinding 15 at equidistaiit points by means of leads 23,- and thus placedin polypliasc relation to the winding I5.

Referring now to Fig. 2, 25 represents the end castings and 26 thecenter casting of a motor embodying my invention. These castings areheld together by means of bolts 27. The armature-core 14 is mountedupon. a shaft 2S, journaled in bearings 2t) in the end castings 25.Mounted on the shaft 28 is a cup-shaped member 30, which carries thecommutator-segments 17. In practice the inner ends of thesecominutator-seginents 17 form the terminals 21 (Shown in Fig. 1Slidingly mounted on the shaft 2S within the cup-shaped member 30 is amember 31 which carries a number of contact-making devices correspondingto the contact-riiig 2() of Fig. l. When the motor is at rest, thesecontact?l pieces 2O rest upon a conducting-ring 32, carried in thecup-shaped member 30. The ineinber 31 is held in its normal position bymeans of a coil-spring 33. The members 30 and $31 are beveled on theiropposing faces and have placed between them wedge-shaped weights 34.After the motor has attained a predetermined speed the centrifugalaction of the Wedge-shaped weights 34 will force the inember 31 alongthe shaft 28, and thus connect the various comniutator-segments I7 withthe conducting-ring 32, thus short-circuiting the individual coils ofthe aiinatiire.

In the modification shown in Fig. 3 the winding 15 is connected to thecoininutatorsegments in the same maimer as has been above described, andthe individual coils are sliort-circuited in the same manner. Thewinding 15, however, is not connected to the resistance 22; but aseparate winding SS is provided which is connected, by means of leads39, with slip rings 40. Bearing on. these slip-rings are contacts 41, towhich are connected the leads 23 from the resistance 22. In thisconstruction the resistance 22 is provided with contacts 42. These con-IOO tacts cooperate with a three-armed switch 43, by means of which theresistance maybe gradually cut out of circuit.

Referring now to Fig. 4, it will be seen that in the modification of myinvention there shown the armature-core 14 is provided with but a singlewinding 15, similar to Fig -1, instead of with two independent windings,as shown in Fig. 3, and that both the commutator 17 and the variableresistance 22 are connected in circuit with the winding 15. In operatingthis form of my motor, and referring particularly to Figs. 1 and 2,singlephase alternating current is 'fed to the fieldcoils 11 Afrom themains 12. This induces single-phase currents in the armature-coils 15.As these coils are commuted by a commutator 17 and brushes 1S, the motoris selfstarting, as is well known. In addition to the single-phasecurrent in the armaturecoils 15, however, polyphase currents will beinduced, owing to the connection of the resistance 22 in polyphaserelation with the said coils, and these polyphase currents aid instarting the motor. T his resistance may be varied, if desired, ashereinafter described. After the motel' has reached speed the individualcoils of the circuit 15 will be automatically short-circuited by the-contact-ring 2O and the motor will continue to run at normal speedunder load. In the modification shown in Fig. 3 the resistance 22 iscontained in a separate circuit. In this construction after the armaturehas reached speed the resistance 22 may be gradually eut out by means ofthe three-armed switch 43. It is evident that by varying the amount ofthe resistance 22, included in the armature circuit or circuits, thespeed of the motor, when running below normal, may be varied at will. Asthe modification shown in Fig. 4 differs from that of Fig. 3 only inthat the armature of Fig. 4 is provided with but a single winding, it isthought that its operation will be obvious from the above.

Having fully described my inventionvhat I claim as new, and desire tosecure byLetters Patent of the United States, isv

1. The combination with one of the members of an alternating-currentmotor, of a conductor connected at a plurality of points to said memberto form a short circuit therefor, a second conductor connected to saidmember, means for determining the position of the poles of said member,and means for short-circuiting said second conductor.

2. The combination with one of the members of an alternating-currentmotor, of a conductor containing a resistance and connected at aplurality of points to said member to form a short circuit therefor, asecond conductor connected to said member, means for determining theposition of the poles of saidv member, and means vfor short-eircuitingsaid second conductor.

The combination with one of the members of an alternating-current motor,of a conductor containing a variable resistance and connected at aplurality of points to said member to form a short circuit therefor, asecond conductor connected to said menlber, means for determining theposition of the poles of said member, and means for shortcircuiting saidsecond conductor.

4. The combination with one of the members of an alternating-currentmotor, of a winding therefor, a conductor connected at a plurality ofpoints to said winding to 'form a short circuit therefor, a secondconductor connected to said winding, means connected with said secondconductorl for determining the position of the poles of said member, andmeans for short-circuiting said winding.

5. The combination with one of the members of an alternating-currentmotor, of a conductor connected in polyphase relation thereto to form ashort circuit therefor, a sccond conductor for said member, means fordetermining the position of the poles of said member, and means forshort-circuiting said second conductor.

6. In an electric motor, the combination with field-coils, of anarmature having a commuted circuit at starting, a resistance connectedin polyphase relation to said armature, and .means in addition to faidpolyphase connectionsfor short-circuiting individual coils of thearmature after starting.

7. In an electric motor, the cmnbination with field-coils,of an armaturehaving a columuted circuit at starting, a resistance connected inpolyphase relation to said armature, and automatic means forshort-circuiting individual coils of the armature after starting.

S. In an electric motor, the combination with field-coils,of an armaturehaving a commuted circuit at starting, a resistance connected inpolyphase relation to said armature, and means for short-circuitingindividual coils of said commuted circuit after starting.

9. In an electric motor, the con'ibination with field-coils, of anarmature having coinmuted circuit at starting, a resistance connected inpolyphase relation to said armature, and automatic means forshort-circuiting the individual coils of said commuted circuit afterstarting.

10. In an electric motor, the combination with field-coils,of anarmature having a conimuted circuit at starting, a resistance connectedin polyphase relation to said commuted circuit, and means forshort-circuiting the individual coils of said commuted circuit afterstarting.

11. In an electric motor, the combination with field-coils,of anarmature having a commuted circuit at starting, a resistance connectedin polyphase relatiiin to said commuted circuit, and means forautomatically short-eireuiting the individual coils of said eommutedcircuit after starting.

12. In an alternating-Current motor, the combination of lleld-eoils, ofan armature having a oommuted Circuit at starting7 a variable resistanceconnected in polyphase relation to said armature, and means in additionto the polyphase connections for short-oirouiting individual coils ofthe armature after starting.

13. In an alternating-current motor, the combination with field-coils,of an armature having a eommuted circuit at starting7 a variabloresistance connected in polyphase relation to said eominuted Circuit,and means in addition to the polyphase connections for

